Fiona Hill says Putin got 'frustrated many times' with Trump because the Russian leader 'had to keep explaining things' to him

• Putin often became frustrated with Trump over his lack of knowledge on big issues, Fiona Hill said.
• "He had to keep explaining things, and Putin doesn't like to do that," Hill said.

Russian President Vladimir Putin often became frustrated with President Donald Trump over his lack of knowledge on geopolitical issues, Fiona Hill said, adding that this played into Moscow's decision on the timing of Russia's invasion of Ukraine.

One of the reasons Putin invaded Ukraine with President Joe Biden in the White House was that he expected the US to "sue for peace" and thought it would be better to deal with Biden than trying to negotiate with someone like Trump, whom the Russian leader had "to explain everything to all the time," Hill, who served as the top Russia advisor on the National Security Council under Trump, said Tuesday at a Chicago Council on Global Affairs event.

"He thought that somebody like Biden — who's a transatlanticist, who knows all about NATO, who actually knows where Ukraine is, and actually knows something about the history, and is very steeped in international affairs — would be the right person to engage with," Hill said.

"You could see that he got frustrated many times with President Trump because he had to keep explaining things, and Putin doesn't like to do that," Hill said, adding: "Even though he loves to be able to spin his own version of events, he wants to have predictability in the person that he's engaging with."

A number of Trump's former advisors have said the ex-president had a poor grasp of global affairs. The former national security advisor John Bolton, for example, said Trump once asked whether Finland was part of Russia.

Similarly, Trump's former White House chief of staff Gen. John Kelly also once said Trump "doesn't know any history at all, even some of the basics on the US," says Hill's new book, "There Is Nothing for You Here: Finding Opportunity in the Twenty-First Century," which was published last year.

In the book, Hill writes that Trump's meager comprehension of international affairs was a "major liability" for US national security.

"Whenever he got to meetings and the conversation started, it seemed like the first time he was hearing things from world leaders," she writes.

Trump did not immediately respond to Insider's request for comment.